Certain medical procedures include the use of a guide wire that is passed through one or more tubular vessels in the body, such as blood vessels. Among these procedures are (a) percutaneous transluminal coronary angioplasty (PCTA), wherein a balloon catheter is steered through a blood vessel to a given location and inflated in order to dilate a coronary artery, (b) stent or stent graft insertion, (c) blood vessel stripping. (d) blood vessel harvesting, (e) angiography, and (t) percutaneous transluminal angioplasty.
For procedures involving a blood vessel the guide wire is typically introduced into a vessel via an opening made by a surgeon. For example, a guide wire may be introduced through a small needle hole made in the femoral artery in the groin area. The guide wire may then be maneuvered through the femoral artery and aorta and into branches of the vascular system until it reaches the desired location in the desired vessel. Maneuvering the guide wire requires the surgeon to apply torque to the end of the wire outside of the body (the “proximal end”) to twist or rotate the wire, thereby changing the position of the end of the wire inside the body (the “distal end”) to guide it into openings to branch vessels.
Guide wires often have a slippery, hydrophilic coating to provide high lubricity thus allowing the wire to pass easily through an organ, such as a blood vessel. However, such guide wires may be so slippery that sufficient torque cannot be applied by simply rolling or twisting the proximal end of the guide wire between a thumb and forefinger. Consequently, a torque device is needed to grip the guide wire for adequate torque to be applied.
Traditional torque devices are comprised of a small tube, or body portion, having an opening therethrough. At one end of the tube is a structure, such as a collect having four fingers that can be pressed together to grip the guide wire. A screw cap having a hole for the passage of the guide wire therethrough is secured to the tube, is positioned over the collet and has a tightened position and a loosened position. As the cap is moved to the tightened position, the fingers are compressed radially inward, gripping the guide wire positioned between them. The guide wire can then be manipulated by turning or twisting the torque device.
A drawback of known torque devices is that the guide wire can only be threaded from one end, i.e., through the cap positioned at one end of the torque device, which may make the device difficult to thread in the operating room. Additionally, known torque devices grip a guide wire at just one location, which does not always sufficiently secure the guide wire to allow the application of adequate torque and/or force for steering or to pull the guide wire taut during certain procedures, such as vein harvesting (during which, additional longitudinal displacement forces may be encountered). Additionally, with known torque devices the guide wire must be advanced or retracted by holding the guide wire in one hand, which can be awkward.
In addition, guide wires are packaged for shipping. A commonly-used guide wire package is a tubular plastic sheath into which the guide wire is placed. Typically, when packaged, an end of the guide wire extends outside of an end of the package and a guide wire director is positioned on the exposed end of the guide wire. The guide wire director has a first end that includes an opening dimensioned to receive the end of the guide wire package, thus securing the director and guide wire during shipping and handling, and a second end that includes an elongated snout, which is used to introduce the guide wire into a lumen, such as the lumen of a vein or catheter. It would be advantageous to provide a torque device that could be preapplied to the guide wire (rather than being applied in the operating room) and that could be positioned on an end of a guide wire package so it remained positioned thereon during shipping. It would also be advantageous if a torque device included a snout to assist in introducing a guide wire into a lumen.